A centrifugal mother liquor ozone destruction system

Abstract

The utility model discloses a centrifugal mother liquor ozone destruction system belongs to polyvinyl chloride production equipment technical field, including bubble tower and ozone destruction device, is equipped with condenser and gas -liquid separator between bubble tower and ozone destruction device, and the air inlet of condenser is connected with the gas outlet of bubble tower, and the gas outlet of condenser is connected with the air inlet of gas -liquid separator, and the gas outlet of gas -liquid separator top is connected with ozone destruction device. The lateral wall of gas -liquid separator is cylindrical structure, and the import of gas -liquid separator is arranged in its lateral wall, and the import is towards the tangent direction of its inner wall, and ozone enters along the tangent direction of gas -liquid separator inner wall, and realizes gas -liquid separation through centrifugal effect. The utility model discloses through condenser and gas -liquid separator cooperation, utilizes two stage gas -liquid separation to remove the water vapor entrained in ozone effectively, solves the problem that the moisture reduces catalyst activity, accelerates catalyst failure, and helps to reduce equipment failure rate.

Description

Technical Field

[0001] This utility model belongs to the technical field of polyvinyl chloride production equipment, and specifically relates to a centrifugal mother liquor ozone destruction system. Background Technology

[0002] In the polyvinyl chloride (PVC) production process, the polymerized and dried PVC slurry is initially separated from PVC resin and water using a centrifuge. The resulting centrifugal mother liquor is then transported to a centrifugal mother liquor ultrafiltration regeneration unit. After treatment, it is ultimately used as the raw water for preparing desalinated water, achieving a closed-loop wastewater utilization effect. Because the centrifugal mother liquor contains a large amount of organic matter, it needs to be degraded aerobically and anaerobically by cultivating bacteria. However, residual bacteria in the system can enter downstream processes with the treated water, affecting the desalinated water production system. Therefore, ozone needs to be added to remove residual bacteria and ensure the quality of the treated water.

[0003] Currently, ozone sterilization systems are widely used in centrifugal mother liquor water treatment. Ozone is used to sterilize the mother liquor through full contact between the primary and secondary bubble towers and the centrifugal mother liquor. Residual ozone is removed by catalytic reaction in the exhaust gas destruction device. However, the residual ozone carries water vapor from the centrifugal mother liquor into the ozone destruction device, reducing the activity of the catalyst (VOD) and the ozone decomposition efficiency. As moisture accumulates, catalyst deterioration is accelerated. Furthermore, the water vapor entering the system equipment can easily cause corrosion, and the equipment is prone to freezing in winter, increasing the equipment failure rate. Utility Model Content

[0004] The purpose of this invention is to provide a centrifugal mother liquor ozone destruction system, which aims to solve the problems existing in the prior art mentioned above.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows: A centrifugal mother liquor ozone destruction system includes a bubbling tower and an ozone destruction device. A condenser and a gas-liquid separator are provided between the bubbling tower and the ozone destruction device. The air inlet of the condenser is connected to the air outlet of the bubbling tower, and the air outlet of the condenser is connected to the air inlet of the gas-liquid separator. The air outlet at the top of the gas-liquid separator is connected to the ozone destruction device. The side wall of the gas-liquid separator has a cylindrical structure, and the inlet of the gas-liquid separator is located on its side wall, facing the tangential direction of its inner wall. Ozone enters along the tangential direction of the inner wall of the gas-liquid separator, and gas-liquid separation is achieved through centrifugal action.

[0006] Furthermore, the top of the gas-liquid separator is provided with multiple layers of stainless steel wire mesh, which is used for secondary gas-liquid separation.

[0007] Furthermore, the liquid inlet of the condenser is connected to a liquid supply pipe, the liquid supply pipe is equipped with a first self-regulating valve, the liquid outlet of the condenser is connected to a liquid return pipe, the liquid return pipe is equipped with a remote temperature transmitter, and the remote temperature transmitter and the first self-regulating valve are respectively electrically connected to a DCS control system.

[0008] Furthermore, the DCS control system presets the target temperature range of the coolant in the return pipe to be 20-25℃.

[0009] Furthermore, the bottom drain of the gas-liquid separator is connected to a recovery pipe, the recovery pipe is equipped with a second self-regulating valve, the gas-liquid separator is equipped with a remote liquid level transmitter, and the DCS control system is electrically connected to the second self-regulating valve and the remote liquid level transmitter respectively.

[0010] Furthermore, the liquid supply pipe is provided with a first bypass pipe to the first self-regulating valve, the first bypass pipe is provided with a first control valve, and manual valves are provided on both sides of the first self-regulating valve.

[0011] Furthermore, the recovery pipe is provided with a second bypass pipe connected to the second self-regulating valve, the second bypass pipe is provided with a second control valve, and manual valves are provided on both sides of the second self-regulating valve.

[0012] Compared with the shortcomings and deficiencies of the prior art, the present invention has the following beneficial effects.

[0013] This invention provides a centrifugal mother liquor ozone destruction system. The condenser cools the high-temperature and high-humidity ozone gas, and then the gas is separated by centrifugal force generated by the tangential inlet of the gas-liquid separator. The system is further separated by a multi-layer stainless steel wire mesh on top for secondary retention. This dual action significantly improves the dehydration efficiency, effectively removes water vapor entrained in the ozone, prevents moisture from reducing catalyst activity and accelerating catalyst failure, and reduces corrosion and freezing problems in the system equipment caused by water vapor, thereby lowering the equipment failure rate. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the pipeline connection structure of the centrifugal mother liquor ozone destruction system in this utility model.

[0015] In the diagram: 1. Bubble tower; 2. Condenser; 3. Gas-liquid separator; 4. Ozone destructor; 5. Liquid supply pipe; 6. Liquid return pipe; 7. First automatic control valve; 8. Remote temperature transmitter; 9. First bypass pipe; 10. First control valve; 11. Inlet; 12. Stainless steel wire mesh; 13. Second automatic control valve; 14. Remote liquid level transmitter; 15. Second bypass pipe; 16. Second control valve; 17. Recovery pipe. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0017] Reference Figure 1 This utility model discloses a centrifugal mother liquor ozone destruction system, which includes a bubbling tower 1, a condenser 2, a gas-liquid separator 3 and an ozone destruction device 4 connected in sequence by pipelines. The components work together to complete the dehydration treatment of high temperature and high humidity ozone.

[0018] The centrifuged mother liquor is thoroughly mixed and contacted with ozone inside the bubble column 1. The strong oxidizing properties of ozone kill any remaining bacteria in the mother liquor. The top of the bubble column 1 has an outlet, which is sealed to the inlet of the condenser 2 via a pipe. The high-temperature and high-humidity ozone gas generated after sterilization is transported to the condenser 2 for cooling through this pipe.

[0019] The condenser 2 is equipped with an independent coolant circulation system. The inlet of the condenser 2 is connected to the supply pipe 5 to continuously supply coolant into the condenser 2; the outlet is connected to the return pipe 6, through which the coolant after heat exchange with ozone gas is discharged and participates in the circulation. The outlet of the condenser 2 is sealed to the inlet 11 of the gas-liquid separator 3 via a pipe.

[0020] A first self-regulating valve 7 is installed on the supply pipe 5 to precisely regulate the flow rate of coolant entering the condenser 2, thereby controlling the heat exchange efficiency of the condenser 2. A remote temperature transmitter 8 is installed on the return pipe 6 to monitor the temperature of the coolant after heat exchange in the return pipe 6 in real time. The remote temperature transmitter 8 can be a commercially available SBWZ series integrated temperature transmitter (Pt100 platinum resistance), with a measurement range of -50℃ to 200℃ and an accuracy of ±0.2% FS. The first self-regulating valve 7 and the remote temperature transmitter 8 are electrically connected to the DCS control system. The DCS control system presets a target temperature range for the coolant in the return pipe 6. A remote temperature transmitter 8 monitors the coolant temperature in real time and sends the data to the DCS control system. The DCS control system compares the detected temperature with the preset target temperature range. When the detected temperature exceeds the upper limit of the target temperature, the first automatic control valve 7 increases its opening, increasing the coolant flow rate to improve the condenser's cooling performance. When the detected temperature is below the lower limit of the target temperature, the first automatic control valve decreases its opening, thereby reducing the coolant flow rate and decreasing the coolant's cooling performance. In this embodiment, the target temperature range for the coolant in the return pipe is 20-25°C.

[0021] Both the supply pipe 5 and the return pipe 6 are equipped with manual valves. The supply pipe 5 is connected to the first bypass pipe 9 in parallel with the first automatic control valve 7. The first bypass pipe 9 is equipped with the first control valve 10. The first bypass pipe 9 is used as a backup channel. When the first automatic control valve 7 fails, the pipe where the first automatic control valve 7 is located can be closed by the manual valve, and the first control valve 10 can be opened at the same time to connect the first bypass pipe 9, so as to ensure continuous production.

[0022] The upper part of the gas-liquid separator 3 is a cylindrical structure. The arc-shaped sidewall of the gas-liquid separator 3 is provided with an inlet 11, and the orientation of the inlet 11 is consistent with the tangent direction of the arc-shaped sidewall. After the ozone enters the gas-liquid separator 3 through the inlet 11, it achieves a single gas-liquid separation through centrifugal action. The ozone flows upward and the liquid flows downward. The top of the gas-liquid separator 3 is provided with an exhaust port, which is connected to the ozone destruction device 4 through a pipe. The bottom of the gas-liquid separator 3 is provided with a drain port, which is connected to a recovery pipe 17. The recovery pipe 17 is connected to the downstream recovery and treatment equipment for recovering the separated liquid.

[0023] The top of the gas-liquid separator 3 is equipped with a multi-layer stainless steel wire mesh 12 for secondary gas-liquid separation. The overall thickness of the multi-layer stainless steel wire mesh 12 is 50cm.

[0024] A second automatic control valve 13 is installed on the recovery pipe 17 to control the opening and closing of the recovery pipe 17. A remote liquid level transmitter 14 is installed on the gas-liquid separator 3 to detect the liquid level inside the gas-liquid separator 3 in real time. The remote liquid level transmitter 14 can be a commercially available CYB-208 submersible liquid level transmitter. Both the second automatic control valve 13 and the remote liquid level transmitter 14 are electrically connected to the DCS control system. The DCS control system presets a liquid level threshold. When the liquid level in the gas-liquid separator 3 reaches the preset height, the remote liquid level transmitter 14 sends a signal to the DCS control system, and the second automatic control valve 13 opens the recovery pipe 17, discharging the liquid in the gas-liquid separator 3 through the recovery pipe 17. In this embodiment, the preset liquid level is 50% of the detection range.

[0025] The first and second automatic control valves can be commercially available ZJHP type pneumatic single-seat control valves (equipped with an electric valve positioner), which support 4-20mA standard signal output and can be directly linked with the DCS control system to achieve automatic opening adjustment.

[0026] Manual valves are installed on both sides of the second automatic control valve on the recovery pipe 17 to control the opening and closing of the pipeline where the second automatic control valve 13 is located. At the same time, a second bypass pipe 15 is provided on the recovery pipe 17 in parallel with the second automatic control valve 13. A second control valve 16 is installed on the second bypass pipe 15. The second bypass pipe 15 serves as a backup channel. When the second automatic control valve 13 malfunctions, the pipeline where the second automatic control valve 13 is located can be closed by the manual valve, and the second control valve 16 can be opened to open the second bypass pipe 15, ensuring smooth production.

[0027] An ozone detector is installed near the gas-liquid separator 3. This ozone detector is electrically connected to the DCS control system, and its detection range covers the surrounding air area of ​​both the gas-liquid separator 3 and the ozone destruction device 4, used for real-time monitoring of the ozone concentration within the area. When the DCS control system determines that the received ozone concentration signal exceeds a preset safety threshold, it will simultaneously trigger the audible and visual alarm function of the ozone detector, and display an alarm notification on the DCS control system interface. This allows personnel to promptly detect and address the risk of ozone leakage, ensuring the safe operation of the equipment and the safety of the on-site working environment.

[0028] When the centrifuged mother liquor ozone destruction system is in operation: The centrifugal mother liquor produced during polyvinyl chloride (PVC) production is fed into bubble column 1 and thoroughly mixed and contacted with ozone. Utilizing the strong oxidizing properties of ozone, residual bacteria in the mother liquor are completely killed. The sterilized, high-temperature ozone gas carrying water vapor is then discharged from the top outlet of bubble column 1 and transported to condenser 2 via pipeline.

[0029] The condenser 2 starts its coolant circulation system, with the supply pipe 5 continuously supplying coolant to the condenser 2 for heat exchange and cooling with the high-temperature ozone gas. The remote temperature transmitter 8 on the return pipe 6 monitors the temperature of the coolant after heat exchange in real time and transmits the data to the DCS control system. When the detected temperature exceeds the preset upper limit of 20-25℃, the DCS control system controls the first automatic regulating valve 7 to increase its opening, thereby increasing the coolant flow rate and improving cooling efficiency. When the detected temperature falls below the preset lower limit, the first automatic regulating valve 7 decreases its opening, reducing the coolant flow rate to maintain a stable cooling effect and ensure that the ozone gas reaches the preset temperature after condensation. If the first automatic regulating valve 7 malfunctions, its two side valves can be closed, and the first control valve 10 of the first bypass pipe 9 can be opened, ensuring continuous operation of the condensation process through the first bypass pipe 9.

[0030] After being cooled by condenser 2, the ozone gas enters through a pipe via the tangential inlet 11 on the side wall of the gas-liquid separator 3. Utilizing centrifugal force, most of the liquid water vapor in the gas is thrown towards the inner wall of the separator and settles downwards, achieving primary gas-liquid separation. Subsequently, the ozone gas flows upwards, passing through the multi-layer stainless steel wire mesh 12 at the top of the gas-liquid separator 3. Residual tiny droplets are trapped by the wire mesh, completing secondary gas-liquid separation and ensuring that the discharged ozone gas meets the required dryness standard.

[0031] During the gas-liquid separation process, the settled liquid collects at the bottom of the gas-liquid separator 3. The remote liquid level transmitter 14 monitors the liquid level in real time and feeds it back to the DCS control system. When the liquid level reaches a preset threshold of 50% of the detection range, the DCS control system triggers the second automatic control valve 13 to open. The separated liquid is then transported to the downstream recycling and treatment equipment through the recovery pipe 17 to achieve water resource recycling. If the second automatic control valve 13 malfunctions, its two side hand valves can be closed, and the second control valve 16 of the second bypass pipe 15 can be opened to discharge the liquid through the backup channel, preventing liquid overflow from the separator.

[0032] The dried ozone gas, after undergoing two stages of dehydration, is discharged from the exhaust port at the top of the gas-liquid separator 3 and enters the ozone destruction device 4. Under the action of a catalyst within the device, residual ozone is completely catalytically decomposed, preventing exhaust gas pollution. Simultaneously, an ozone detector near the gas-liquid separator 3 monitors the surrounding ozone concentration in real time, transmitting the detection signal to the central control room computer. If the concentration exceeds the standard, an alarm is immediately triggered to ensure production safety.

[0033] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A centrifugal mother liquor ozone destruction system, comprising a bubbling tower (1) and an ozone destruction device (4), characterized in that, A condenser (2) and a gas-liquid separator (3) are provided between the bubbling tower (1) and the ozone destruction device (4). The inlet of the condenser (2) is connected to the outlet of the bubbling tower (1), and the outlet of the condenser (2) is connected to the inlet (11) of the gas-liquid separator (3). The outlet at the top of the gas-liquid separator (3) is connected to the ozone destruction device (4). The side wall of the gas-liquid separator (3) is a cylindrical structure. The inlet (11) of the gas-liquid separator (3) is located on its side wall, and the inlet (11) faces the tangential direction of its inner wall. Ozone enters along the tangential direction of the inner wall of the gas-liquid separator (3) and gas-liquid separation is achieved through centrifugal action.

2. The centrifugal mother liquor ozone destruction system as described in claim 1, characterized in that, The gas-liquid separator (3) has a multi-layer stainless steel wire mesh (12) at its top.

3. The centrifugal mother liquor ozone destruction system as described in claim 1, characterized in that, The condenser (2) is connected to a liquid supply pipe (5) at its inlet. The liquid supply pipe (5) is equipped with a first self-regulating valve (7). The condenser (2) is connected to a return pipe (6) at its outlet. The return pipe (6) is equipped with a remote temperature transmitter (8). The remote temperature transmitter (8) and the first self-regulating valve (7) are electrically connected to a DCS control system.

4. The centrifugal mother liquor ozone destruction system as described in claim 3, characterized in that, The DCS control system presets the target temperature range of the coolant in the return pipe to be 20-25℃.

5. The centrifugal mother liquor ozone destruction system as described in claim 3, characterized in that, The bottom drain of the gas-liquid separator (3) is connected to a recovery pipe (17), the recovery pipe (17) is equipped with a second self-control regulating valve (13), the gas-liquid separator (3) is equipped with a remote liquid level transmitter (14), and the DCS control system is electrically connected to the second self-control regulating valve (13) and the remote liquid level transmitter (14) respectively.

6. The centrifugal mother liquor ozone destruction system as described in claim 3, characterized in that, The liquid supply pipe (5) is provided with a first bypass pipe (9) connected to the first self-regulating valve (7). The first bypass pipe (9) is provided with a first control valve (10). Hand valves are provided on both sides of the first self-regulating valve (7).

7. The centrifugal mother liquor ozone destruction system as described in claim 5, characterized in that, The recovery pipe (17) is provided with a second bypass pipe (15) connected to the second self-regulating valve (13). The second bypass pipe (15) is provided with a second control valve (16). Manual valves are provided on both sides of the second self-regulating valve (13).

Images